Marine biologists have called on the fishing nations of the world to end government subsidies of fishing fleets that are plundering the deep seas and permanently stripping the ocean floor of its unique lifeforms.
Fish that live for more than 100 years and cold-water coral reefs that have taken millennia to form are being destroyed by the "roving bandits" of the high seas that could not survive without government aid.
Government subsidies are being used to prop up the international trade in deep-sea fishing that is causing the serial and long-term depletion of the deep seabed, the scientists said.
Japan, South Korea, Russia and Spain lead the list of nations that are sanctioning the pillage of the deep ocean with public money which is diverted into subsidies to pay to fuel and equip trawlers, the scientists said.
Robert Steneck, a fisheries expert at the University of Maine, said: "The unregulated catches of these roving bandits are utterly unsustainable. With globalised markets, the economic drivers of over-fishing are physically removed and so fishermen have no stake in the natural systems they affect.
"While it may be a good short-term business practice to fish out stocks and move on, we now see global declines of targeted species," Dr Steneck told the American Association for the Advancement of Science in San Francisco.
"The solution is not going into the deep sea but better managing the shallow waters where fish live fast and die young, and ecosystems have a greater potential for resilience," he said.
A study found that more than $152m (£78m) in government subsidies was paid each year to maintain deep-sea trawling vessels around the world. Without that money, the international business would run at a loss of about $50m a year.
Most of the subsidies are used to pay for the fuel needed to sail beyond the 200-mile, economic exclusion zones - far enough out to areas where international rules about fishing are so lax that conservationists refer to it as the least-protected place on Earth.
Deep-sea trawling involves dragging 15-ton weights across the seabed to break up corals and rocks so that fish can be scooped up into vast nets.
The trawling is so fuel-intensive that it takes between 5kg and 8kg of fuel to catch 1kg of fish, according to Daniel Pauly of the University of British Columbia.
"There is surely a better way for governments to spend money than by paying subsidies to a fleet that burns 1.1 billion litres of fuel annually to maintain paltry catches of old-growth fish from highly vulnerable stocks, while destroying their habitat in the process," he said.
"Eliminating global subsidies would render these fleets economically unviable," he said.
As fish stocks around shallow, continental shelves have declined and collapsed, fishing fleets have gone further afield into deeper waters to catch fish that in previous decades were considered too low value to be worthwhile.
Selina Heppell of Oregon State University said deep-sea species such as the orange roughy and Chilean sea bass are very slow to grow and can take many years to reach sexual maturity. "When you buy orange roughy, you are probably purchasing a fillet that is at least 50 years old. Most people don't think of the implications of that - perhaps we need a guideline that says we shouldn't eat fish as old as our grandmother," she said.Reuse content